I have noticed that Penske Camaros used the Stewart-Warner electrical oil pressure sender and thus an electrical gauge, rather than a mechanical one. It seems like most other Camaro racing engines did not use the electrical sender & gauge. Any thoughts as to why the Penske team went with these over the mechanical sender & gauge? Easier to hook up, but same accuracy?

I'm thinking that they felt it was more reliable and less prone to damage during a race. The fact is if you lose INTERNAL oil pressure your probably done for the day. If the mechanical oil pressure line gets damaged, burned,cracked etc or done as well. However, if just the wire gets wounded your still in the race.

It could be just to make engine change easier with just the wire vs an oil line but have seen some old race cars that ran a cooper line off the back of the engine near dist. where the stock oil light sensor is.

I have seen some run a tee there to use the oil light and the mach gauge at same time.Maybe Penske used a oil light on the front and mech gauge in the rear?

also there was always rumor of Penske tricks. have heard of a pressurized oil tank system that would boost oil pressure if it sensed a low oil press condition such as in a high speed high banked corner. Maybe that electric oil pressure senor could be part of such a system?

On the power brake booster....there was a story about Penske using a reverse vacuum system that would pull back the brake caliber pistons for a quick brake pad change in a pit stop. not sure if it was true

On the power brake booster....there was a story about Penske using a reverse vacuum system that would pull back the brake caliber pistons for a quick brake pad change in a pit stop. not sure if it was true

It was indeed true, and it worked very well, it just used engine vacuum, and they could change pads as quickly as they could grab them.I know that one of those systems, or the parts to make one, still exist with one of the original T/A drivers.

I had a recent conversation with Bill Howell who worked for Vince Piggins' group and was directly involved as the Chevy liason with Trans-Am from 1968-70. Part of our conversation touched on the subject of brakes and here is some of what he said...

"Penske ran 2 cars in the 68 Sebring, both with 2X4's. We won the Trans-am part of [the 1968 Sebring race] after getting tromped by the Fords at the 24 hr of Daytona. We beat them mainly with a brake pad change trick I developed between Daytona and Sebring. It took a year or more for Ford to figure out what it was. It was a simple idea where we applied vacuum to the master cylinder to draw the disc brake pistons back into the calipers, releasing the pressure on the pads. We took the vacuum off the brake booster. We tapped off the brake booster thru a vacuum switch (same as used on the old Corvette headlight doors), controlled by a switch on the dash, then to the cover over the master cylinder. [Coming into the pits] they did need to blip the motor to get vacuum into the booster. Only the Penske cars were equipped this way, as I took the hardware with me when I went to Sebring before the race weekend to keep it secret. The system was mentioned in Van Valkenburg's book. The reason it took Ford so long to figure it out was it was so simple, and most people thought that if you put a vacuum on the brake calipers, it would suck air past the seals and into the fluid."

"Yes, I suspect or remember that they used an electrical oil pressure guage. They weren't too concerned about the accuracy, only that they had pressure. In fact I discovered by accident that Mark, and most other good drivers, were too busy to give good feedback on oil pressure, unless they happened to look at it on a straightaway. We [all Trans-Am teams] had many failures due to oil pressure loss (particularly the Fords) because we were forced to use the stock oil pan. And, only with telemetry were we able to get good feedback. As a further insight, a mechanical oil pressure line and gauge is a potential oil leak."